Removing Soluble Support Material From Rapid Prototype Part

ABSTRACT

A container has been devised for use with a rapid prototype part making machine, specifically of the type having Fused Deposition Modeling (FDM) capabilities. The container includes a liner that has an exterior surface and that is expandable to define a mouth portion and a volume for receiving, via the mouth portion, a rapid prototype part having soluble support material deposited on the rapid prototype part. An inlet port is formed on the exterior surface and is in fluid communication with the volume. An outlet port is formed on the exterior surface and is in fluid communication with the volume. A sealing arrangement is configured and arranged to selectively substantially prevent egress of an aqueous cleaning solution from the mouth portion of the liner. The inlet port is configured to introduce the aqueous cleaning solution into the volume to remove the soluble support material from the rapid prototype part.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 10/991,679, which was filed Nov. 18, 2004, and which claims thebenefit of priority from U.S. Provisional Application Ser. No.60/523,776 filed Nov. 19, 2003, entitled “Apparatus and Method ofRemoving Water Soluble Support Material from a Rapid Prototype Part,”the disclosures of which, including all attached documents, areincorporated herein by reference in their entirety for all purposes.

TECHNICAL FIELD

The present disclosure relates generally to processes for creating rapidprototype parts. More particularly, the present disclosure relates toremoving temporary support material generally utilized in the productionof rapid prototype parts.

TECHNICAL BACKGROUND

Fused Deposition Modeling (FDM) is one method among a few capable ofdeveloping rapid prototype parts or functional models from athermoplastic material such as ABS (acrylonitrile butadiene styrene) andpolycarbonate. FDM utilizes a computer numeric controlled (CNC)extruder-head which squeezes a fine filament of melted thermoplasticthrough a modeler nozzle. The controller, operating in accord withpre-select, known variables, activates the modeler nozzle to depositheated plastic layer-by-layer to form the desired geometric shape. Insome instances where select features of the part are left unsupported asa result of the part's orientation, the FDM-based machine mayincorporate the use of a second nozzle for extruding therethroughsupport material to create support structures for any cantileveredportions of the part. In cases where the part's build comprises small,intricate features, a water soluble support material may be used tofurther facilitate or ease removal from the part's build uponcompletion. Once the appropriate supporting layer is built,thermoplastic, as discussed above, is extruded through the modelernozzle to form the part's build. Once the part has finished itssuccessive layers and the build is complete, the part is removed fromthe FDM-based machine for inspection and final surface preparation,which may include removal of any support material, additional machining,and/or application of a finish coating material.

In instances where a water soluble support material is used, the artoffers a range of techniques for removing the support material from therapid prototype part. One such technique may simply involve immersingthe part in a suitable solvent repeatedly via manual or automated meansand manually removing the support material using a brush or a pointedtool. Another technique commonly employed in the art may involveplacement within a conventional immersion parts washer of the typegenerally designed to remove grease, carbon, resins, tar, and otherunwanted petroleum-based residuals from automotive parts and machineshop equipment. Typically, the conventional immersion parts washer ofthis type may comprise operable features of ultrasonics to facilitatethe cleansing action of the solvent. Although the operable feature notedabove may or may not adequately address the removal of support material,the conventional immersion parts washer can be costly in terms ofpurchase, maintenance and operation, particularly for this limitedpurpose, and inappropriate in a variety of environmental settings. Giventhat most machinery having rapid prototype part making capabilities isoperated from within an office setting or a similarly suitedenvironment, the coinciding use of a conventional immersion parts washermakes it unacceptable and inappropriate in maintaining a sound, cleanenvironment. Further, some conventional immersion parts washer mayexpose one to unacceptable health risks, particularly those havingultrasonic capabilities (see World Health Organization Report onUltrasound and Ultrasonic Noise, Geneva 1982).

Accordingly, there remains a need for a dedicated apparatus capable ofremoving water soluble support material from a rapid prototype part andoperating side-by-side with a rapid prototype part making machinecommonly placed and operated in an office setting or a similarly suitedenvironment.

SUMMARY OF THE DISCLOSURE

According to various example embodiments, a container has been devisedfor use with a rapid prototype part making machine, specifically of thetype having Fused Deposition Modeling (FDM) capabilities. The containerdefines a volume that can receive the rapid prototype part, as well asan aqueous solution for removing support material from the rapidprototype part. The container has an inlet port for introducing theaqueous solution into the volume and an outlet port for releasing theaqueous solution from the volume.

In accordance with one example embodiment, a container includes a linerthat has an exterior surface and that is expandable to define a mouthportion and a volume for receiving, via the mouth portion, a rapidprototype part having soluble support material deposited on the rapidprototype part. An inlet port is formed on the exterior surface and isin fluid communication with the volume. An outlet port is formed on theexterior surface and is in fluid communication with the volume. Asealing arrangement is configured and arranged to selectivelysubstantially prevent egress of an aqueous cleaning solution from themouth portion of the liner. The inlet port is configured to introducethe aqueous cleaning solution into the volume to remove the solublesupport material from the rapid prototype part.

According to another embodiment, a method of removing soluble supportmaterial from a rapid prototype part involves placing the rapidprototype part in a container having an inlet port and an outlet port.The container is substantially sealed to selectively substantiallyprevent egress of an aqueous cleaning solution from the container. Thefirst port is connected to a supply of the aqueous cleaning solution.The aqueous cleaning solution is introduced solution into the containervia the inlet port, thereby removing the soluble support material fromthe rapid prototype part. The aqueous cleaning solution is evacuatedfrom the container via the outlet port.

Yet another embodiment is directed to a system for removing solublesupport material from a rapid prototype part. The system includes abasin having an inlet port and a drain basket and configured to store anaqueous cleaning solution. A container includes a liner having anexterior surface. The liner is expandable to define a mouth portion anda volume for receiving, via the mouth portion, a rapid prototype parthaving soluble support material deposited on the rapid prototype part.An inlet port is formed on the exterior surface and is in fluidcommunication with the volume. An outlet port is formed on the exteriorsurface and is in fluid communication with the volume. A sealingarrangement is configured and arranged to selectively substantiallyprevent egress of an aqueous cleaning solution from the mouth portion ofthe liner. A pump is in fluid communication with the basin and isconfigured to pump the aqueous cleaning solution from the basin into thevolume defined by the liner of the container and back to the basin. Whenthe pump is actuated, the aqueous cleaning solution is introduced intothe volume defined by the liner of the container to remove the solublesupport material from the rapid prototype part.

Additional objects, advantages, and features will become apparent fromthe following description and the claims that follow, considered inconjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

Various embodiments will now be described by way of example withreference to the accompanying drawings, in which:

FIG. 1 is a perspective view of one example embodiment illustrating asupport removal apparatus equipped with a basket;

FIG. 2 is a side cross sectional view of the embodiment of FIG. 3 takenon line 2-2 of FIG. 3 illustrating a manifold assembly and strainerbasket situated within an interior chamber;

FIG. 3 is a top view of the embodiment of FIG. 1 illustrating a worksurface mounted to a retention tank;

FIG. 4 is a side cross sectional view of the embodiment of FIG. 3 takenon line 4-4 of FIG. 3 illustrating a strainer basket and a manifoldassembly;

FIG. 5 is a perspective view of the embodiment of FIGS. 1 and 3illustrating a support removal apparatus equipped with a lid;

FIG. 6 is a side cross sectional view of the embodiment of FIGS. 1 and 3illustrating an alternative manifold assembly having an elongate tubularmember;

FIG. 7 is a side cross sectional view of the embodiment of FIGS. 1 and 3illustrating an alternative manifold assembly having an elongate tubularmember connected to an inlet fitting;

FIG. 8 is a partial side cross sectional view of the embodiment of FIGS.1 and 3 illustrating an elongate tubular member connected to a secondend of an outlet piping;

FIG. 9 is a functional block diagram illustrating functionalrelationships between a microprocessor, a thermocouple, pump, heatingelement, and level indicator;

FIG. 10 is a perspective view of another example embodiment illustratinga retention tank equipped with a box manifold;

FIG. 11 is a side cross sectional view of the embodiment of FIG. 10taken on line 11-11 of FIG. 13 illustrating a drain box fitted with anintake side;

FIG. 12 is a side cross sectional view of the embodiment of the FIG. 13taken on line 12-12 of FIG. 13 illustrating a box manifold and heatingelement mounted therebelow and encased in a heat chamber;

FIG. 13 is a side elevational view of the embodiment of FIG. 10illustrating a drain box and box manifold mounted to a retention tank;

FIG. 14 is a side cross sectional view of the embodiment of FIG. 10taken on line 14-14 of FIG. 10 illustrating a box manifold and a heatingelement mounted therebelow and a drain box positioned across therefrom;

FIG. 15 is a front elevational view of the embodiment of FIG. 10illustrating a box manifold;

FIG. 16 is a side cross sectional view of the embodiment of FIG. 15taken on line 16-16 of FIG. 15 illustrating a box manifold;

FIG. 17 is a side cross sectional view of the embodiment of FIG. 15taken on line 17-17 of FIG. 15 illustrating a box manifold;

FIG. 18 is a top view of the embodiment of FIG. 15 illustrating liquidflows through a retention tank equipped with a pump and a three-way ballvalve;

FIG. 19 is a functional block diagram of the embodiment of FIG. 10illustrating functional relationships between a microprocessorcommunicatively coupled to a thermocouple, pump, heating element, levelindicator, and a three-position selector switch;

FIG. 20 is a perspective view of the embodiment of FIG. 10 illustratinga storage cabinet housing a retention tank;

FIG. 21 is a perspective view of the embodiment of FIG. 10 illustratinga drop basket;

FIG. 22 is a front elevational view of the embodiment of FIG. 10illustrating a drop box;

FIG. 23 is a system diagram illustrating a system for removing solublesupport material from a rapid prototype part according to anotherembodiment;

FIG. 24 is a perspective view of a container forming part of the systemof FIG. 23 according to yet another embodiment;

FIG. 25 is another perspective view of the container of FIG. 24;

FIG. 26 is a perspective view of the container of FIGS. 24-25illustrating an open mouth portion;

FIG. 27 is a perspective view of the container of FIGS. 24-25 with asealing arrangement shown as detached from the container;

FIG. 28 is a side view of one example embodiment of the sealingarrangement; and

FIG. 29 is a perspective view of a container having multiple inlet portsand multiple outlet ports according to still another embodiment.

DETAILED DESCRIPTION

While the invention is susceptible of being embodied in many differentforms, various embodiments are illustrated in the accompanying drawingsand are described in detail hereinafter with the understanding that thepresent disclosure is to be considered to exemplify the principles ofthe present invention and is not intended to limit the invention to theembodiments illustrated and presented herein. The embodiments describedherein have particular utility as an apparatus for removing solublesupports from a rapid prototype part produced from a rapid prototypepart making machine such as those that incorporate Fused DepositionModeling (FDM) technology.

Referring now to FIGS. 1-5, there is shown generally at 10 a supportremoval apparatus comprising a tank assembly 12 having means for heatingand agitating an aqueous cleaning solution and a cabinet 14 having aninterface controller 16 mounted on an exterior panel 18 thereof fortemporally controlling heat and agitation outputs. In some embodiments,an aqueous cleaning solution that is well suited for this applicationcomprises a mixture of 25-70 weight percent sodium or potassiumhydroxide and 5-30 weight percent sodium or potassium carbonate,collectively forming a granular sodium or potassium composition suitablefor mixing with water. For example, a concentration ratio of 1.05 poundsof granular sodium or potassium composition per one gallon of watersuitably serves in removing water soluble support material from rapidprototype parts within a tolerable temperature range noted hereinafter.

The tank assembly 12, as shown in FIGS. 2 and 3, comprises a retentiontank 20 having four side walls 22 substantially arranged and connectedto one another to form a box-like structure having a bottom leading edge24 fixedly attached to and along the perimeter of a base 26,collectively forming an interior chamber 28 for containing and holdingthe aqueous cleaning solution. In the illustrated embodiment, anaperture 30 extending through the base primarily serves as means forremoving aqueous cleaning solution from the interior chamber forpurposes of repair and maintenance and like activities. Retention ofaqueous cleaning solution in the interior chamber 28 as well as removaltherefrom and through the aperture is principally controlled by a valve32 connected in line to a drain pipe 34 having an input end 36threadably connected to a drain sleeve 38 mounted to and over theaperture at an exterior side 40 of the base and an output end 42terminating at an external waste line or sump collector.

As shown in FIGS. 1 and 2, one side wall 22 of the retention tankpreferably comprises intake and outlet apertures 44, 46 for passage ofintake and outlet piping 48, 50, respectively, each having first ends 48a, 50 a attached to intake and outlet sides 52 a, 52 b of a pump 52mounted exterior to the retention tank and housed within an interiorportion 54 of the cabinet. Pumps most suited for this applicationcomprise of types having centrifugal or magnetic operable means, to namea couple known in the art to possess favorable characteristics tohydraulically convey and circulate aqueous cleaning solution in andthrough the retention tank 20. However, regardless of the pump typeused, pump seals as well as other operable components thereof arepreferably fabricated from materials which are compatible for use in acorrosive, caustic environment given the alkalinity of the aqueouscleaning solution. Accordingly, seals made from ethylene propylene dienemonomer (EPDM) or VITON® and metallic components made from stainlesssteel tolerably perform well within the predetermined range of operation(temperature and pH) without deleterious impact to pump performance. Asdepicted in FIG. 2, a second end 50 b of the outlet piping 50 isadaptably mounted to a manifold assembly 56 principally serving as meansfor agitating the aqueous cleaning solution contained within theretention tank. In some embodiments, the manifold assembly is housedwithin a portion of the interior chamber 28 and comprises at least onenozzle head 58 threadably mounted to the second end of the outletpiping. In an alternative arrangement, one of which utilizes more thanone nozzle head, the manifold assembly comprises a pipe tree fitting 60having a feed end 62 fixedly attached to the second end 50 b of theoutlet piping and more than one branch ends 64 extending therefrom toevenly distribute the incoming flow into an equivalent number of nozzleheads 58. It is noted herein that the manifold assembly 56 may compriseone or more in number with each being selectively arranged about theretention tank 20 to provide for opposing, cross interaction of flowsfrom each nozzle head, suitably needed in some instances to achieve thedesired level of agitation or turbulence within the interior chamber 28.In this alternative arrangement, the outlet piping is further dividedwith appropriate fittings commonly available in the art and selectivelyconnected to a predetermined number of pipe tree fittings 60 each havingmultiple branch ends 64 fitted with a nozzle head 58. Each nozzle head,as best illustrated in FIGS. 2 and 4, comprises a nozzle tip 66 and athreaded body 68 threadably mounted to each branch end 64. In order todevelop and continually establish a predominate level of agitationwithin the interior chamber, each nozzle tip is suitably configured withan orifice 70 having a diameter ranging from 0.05 to 0.375″. In thisdiametric range combined with a pump capacity ranging from 3-30 gallonsper minute at a power output ranging from 0.04-2 HP, each nozzle tip 66is substantially capable of developing an output pressure ranging from 5to 60 psi, respectively. In this pressure range, each nozzle tipprovides for a jet stream having a tight dispersion pattern capable ofreaching and interacting with and reflecting off the opposing side wallof the retention tank 20 to uniformly agitate the aqueous cleaningsolution within the interior chamber. In instances where the retentiontank comprises a larger volumetric capacity, more than one manifoldassembly 56, as described above, may be needed to create and maintainhomogenous agitation of the aqueous cleaning solution for sustained andcontinued removal of support material from the rapid prototype part(s).In an alternative embodiment, the manifold assembly in lieu of thenozzle head 58 may comprise of an elongate tubular member 72 having aninlet fitting 74 hydraulically attached and extending perpendicularlythereto and a plurality of orifices 76 being positioned about an outerface 78 thereof, substantially in the manner shown in FIG. 6. Assemblyof the elongate tubular member to the second end 50 b of the outletpiping is accomplished by a sleeve 80 having a first end 82 fixedlyattached thereto and a second end 84 having at least two concentricdepressions 86 for accepting therein an equivalent number of O-rings 88.As illustrated in FIG. 8, a free end 90 of the inlet fitting 74 isslidably positioned onto and over the second end 84 and moved thereaboutuntil the O-rings are completely encased within the inner confines ofthe inlet fitting. In the embodiment shown in FIG. 8, each orifice 76situated about the outer face 78 comprises a wall 92 having a anteriorportion 94 a thereof extending perpendicular thereto and a posteriorportion 94 b extending angularly outward a predetermined amount from amidpoint position 94 c in the wall, specifically where the anteriorportion terminates within the confines of the wall.

As illustrated in FIG. 2, a second end 48 b of the intake piping 48comprises a basket strainer 96 having a plurality of apertures 98extending therethrough for passage of the aqueous cleaning solutionduring cyclic circulation thereof while effectively eliminating thepassage of small rapid prototype part(s) and residual support materialsuspended in solution. A backing plate 100 fixedly attached to thebasket strainer and having a threaded coupling 102 fixedly attachedthereto suitably serves as means for mounting the strainer basket to thesecond end of the intake piping, substantially in the manner shown inFIG. 2. To further mitigate undesirable interaction of small rapidprototype part(s) in suspension with the manifold assembly 56 and basketstrainer, where positive and negative pressure is respectively observed,the retention tank 20 is fitted with a plate guard 104 to divide theinterior chamber 28 into first and second compartments 106, 108. In theembodiment of FIG. 2, the plate guard comprises an upper leading edge110 and a plurality of nozzle apertures 112 extending therethrough toaccommodate an equivalent number of nozzle heads 58 for sustained andcontinued passing of the aqueous cleaning solution into the secondcompartment 108 of the interior chamber 28. Mounting of the plate guardwithin the interior chamber is substantially accomplished by attachingthe upper leading edge 110 to a portion of a work surface 114 suitablysituated above and attached to the retention tank. All unattached edgesof the plate guard are selectively positioned away from the side walls22 and base a predetermined distance to form an elongate opening 116therealong, purposefully to maintain circulation of the aqueous cleaningsolution contained within the interior chamber of the retention tank. Toenhance circulation of the aqueous cleaning solution to a greater extentthan that provided by the elongate opening, the plate guard 104 furthercomprises a plurality of openings 104 a collectively positioned near thebottom thereof adjacent to the base 26. Preferably each opening is sizedaccordingly to hinder movement of most rapid prototype part(s) from thesecond compartment into the first compartment, toward the basketstrainer 96, predominantly caused by the presence of negative pressurethereat.

To further assist the cleansing action of the aqueous cleaning solutionfor effective removal of support material from rapid prototype part(s),the retention tank is configurably fitted with a heating element 118having an internal end 120 situated within the interior chamber and anexternal end 122 electrically connected to an output line of amicroprocessor 124. As shown in FIG. 4, the heating element is mountedadjacent to the base in the first compartment 106, specifically beingpositioned most near the side wall where the manifold assembly 56 andbasket strainer are located to facilitate distribution of heat to theaqueous cleaning solution via the pump 52 feeding solution into thefirst and second compartments. Although numerous types of heatingelements may be suited for this application, it has been found that aheating element 118 having a power rating ranging from 50-300 Watts/sq.in., substantially heats the aqueous cleaning solution to 90-180° F.within a modest time range of at least 15-90 minutes, respectively. Theheating element may comprise a variety of geometric configurations anddesign features such as those having an internal end selectively shapedas a band, cable, tubular cartridge, strip, to name a few most widelyknown and available in the art, providing each meets the above operatingspecifications. It is noted herein that certain embodiments mayalternatively employ a heating element mounted externally to theretention tank in lieu of the heating element mounted internally in theinterior chamber. In such embodiments, the retention tank primarilyserves as a suitable conductor in transmitting heat to the aqueouscleaning solution. In similar regard in terms of substantiating thenumber of nozzle heads 58, a retention tank comprising a largervolumetric capacity may necessitate a heating element having a higherheatable surface area and output to maintain the overall effectivenessof the aqueous cleaning solution. Given the operating characteristics ofthe aqueous cleaning solution in terms alkalinity, the internal endpreferably comprises a sheath fabricated from materials such asstainless steel 304 or 316, INCONEL®, INCOLOY®, MONEL™, or titanium,collectively of the type capable of resisting premature failure of theheating element during operative conditions. Working in conjunction withthe heating element, a thermocouple 126 mounted to the retention tank 20suitably serves as means for controlling the temperature of the aqueouscleaning solution within a tolerable range noted hereinbefore. Asdepicted in FIG. 4, the thermocouple comprises an external lead 128electrically connected to the input side of the microprocessor 124 andan internal probe 130 extending inwardly within the first compartmentfor which is readily capable of sensing the ambient temperature of theaqueous cleaning solution and making timely and minute adjustments tothe heating element 118 via the microprocessor. Like the heating elementin terms of material choice, the internal end comprise a sheath 132fabricated from or coated with a material most compatible for operationin a corrosive environment. In addition to the available means forheating and agitating the aqueous cleaning solution, a level indicator134 of the type shown in FIG. 4 provides means for activating power tothe microprocessor to permit activation of a timer switch 136 whichcorrespondingly controls the duration of operating the heating elementand pump 52. Further, the level indicator suitably serves as a safetydevice insofar of eliminating premature activation of the pump when theinterior chamber 28 is absent of aqueous cleaning solution. Levelindicators comprising operable features of optics, magnetic, mechanicalmeans, to name a few commonly available in the art, may be suited forthis application providing each comprises means for connectivity to themicroprocessor 124. As illustrated in FIG. 9, the microprocessorselectively controls outputs to the pump and heating element operablybased on time and temperature set points established by the operator ormanufacturer. In the embodiment shown in FIG. 4, a temperature set pointof approximately 150° F., as set by the manufacturer, establisheseffective performance of the aqueous cleaning solution. Time input, onthe other hand, is selectively controlled by the user via the interfacecontroller 16 comprising means for displaying operating variables oftemperature and time. An example of a suitable microprocessor for thisapplication is the type manufactured by the Watlow Company of St. Louis,Mo., specifically being designated as Watlow Series 935B. It should beunderstood that many other types of microprocessors may be used in thisapplication providing it comprises capabilities to control the desiredoutputs noted above. It is further understood that all electricalcomponents described above, including the pump, heating element,thermocouple, level indicator and microprocessor, may be electricallywired in any known manner. In operation, with reference to FIG. 9, poweris initially supplied to a start switch 137 which subsequently activatesthe level indicator 134. Upon the level indicator detecting the level ofthe aqueous cleaning solution in the retention tank, power is furthertransmitted to the microprocessor, at which time the timer is activatedby the operator to set the temporal limits for operating the pump 52 andheating element 118. Process startup is finally achieved by the operatoractivating a controller start button integrally made part of themicroprocessor. It is noted herein that the heating element onlyoperates within a temperature range of approximately 40° F. to the setpoint of 150° F., notwithstanding the time inputs, in contrast to thepump 52 which operates for the full duration of the time input. Uponexpiration of the timer's set limits, power to the pump as well as theheating element is disabled via the microprocessor 124. Reactivation ofthe cleaning cycle substantially involves re-setting the timer functionand activating the controller start button.

As noted above, the retention tank 20 is fitted with a work surface 138of the type comprising a recessed portion 140 having an opening 142extending therethrough, collectively being contained within an upperledge 144 extending along the perimeter of the work surface. The worksurface, particularly the recessed portion, primarily serves incontaining and channeling the aqueous cleaning solution downwardlytoward the retention tank in the event of inadvertent spillage caused bythe removal of rapid prototype parts from the second compartment 108. Inthe embodiment illustrated in FIGS. 1 and 3, the opening comprises ageometric configuration and size substantially conforming to anaccessible opening 146 of the second compartment. To mitigate furtherloss of aqueous cleaning solution, primarily due to evaporation, thework surface further comprises a lid 148 having a geometricconfiguration substantially conforming to the opening 142 of therecessed portion and a handle 150 fixedly attached to an upper surface152 thereof to provide means for removing and placing the lid onto andover the accessible opening 146. In some applications, the lid, as shownin FIG. 1, is adaptably fitted with a basket 154 hanging downwardlytherefrom for holding small rapid prototype parts which easily suspendin solution and readily move about the interior chamber 28. In thisregard, the basket comprises perforated walls 156 substantially arrangedto form an interior portion 157 capable of containing the rapidprototype parts yet permitting the passing of aqueous cleaning solutionupon removal from the retention tank. In the embodiment shown in FIG. 1,the basket 154 comprises an overall geometric configurationsubstantially capable of fitting within the confines of the secondcompartment 108 and passing unhindered through the opening 142. Accessto the basket is made possible by a parts opening 158 extending throughone of its perforated walls 156 and when placed within the interiorchamber, the parts opening abuts up against the sidewall 22 of theretention tank to impede outgoing flow of rapid prototype parts into theinterior chamber. As illustrated in FIGS. 1 and 5, the cabinet 14further comprises features for operation and maintenance, including anaccess panel 160 removable therefrom to gain access to the pump 52 andother operable components and, as noted earlier, an interface controllerdisplay and the start switch 137 mounted externally on the cabinet. Inmost applications, the work surface 138 is welded to the retention tankand collectively placed into and attached to the cabinet by a pluralityof screws.

An alternative embodiment is shown in FIGS. 10-19. In lieu of themanifold assembly 56 used in the embodiment shown in FIGS. 1-9, theretention tank 20 comprises a large opening 164 to accommodate a boxmanifold 166 having a plurality of nozzle heads 58 for enhancedagitation of the aqueous cleaning solution contained within the interiorchamber and a drain box 168 integrally made part thereof for enhancedcirculation and removal of aqueous cleaning solution from the retentiontank. The box manifold 166 comprises an outer casing 170 having an inletadapter 172 mounted externally thereto and a pressure box 174collectively formed by an inner backside 176 of the outer casing asreinforced by an interior reinforcing plate 178 integrally made part ofthe outer casing and a backing plate 180 used in supporting the nozzleheads 58. As denoted by path E in FIG. 18, the inlet adapter 172 ishydraulically connected to an outlet stem 182 of a three-way ball valve184. As illustrated in FIGS. 16 and 17, the backing plate comprises aplurality of apertures 186 extending therethrough to receive an equalnumber of collars 188 each having internal threads 189. In assembledform, each collar is fixedly attached to the backing plate 180 by a beadof weld placed about its outer circumference, with the threaded body 68of each nozzle head 58 being threadably connected to the collar. Similarto the embodiment shown in FIGS. 1-9 in terms of protecting the nozzlehead from suspended matter, each nozzle tip 66 is positioned within acavity 190 substantially formed by the backing plate and a nozzle plate192 attached thereto by a plurality of screws 194 and the like. In orderto sustain passing of the aqueous cleaning solution into the interiorchamber, yet mitigating the passage of small rapid prototype parts andresidual support material into the box manifold 166, the nozzle platecomprises a plurality of small apertures 196 each being positionallyaligned with each of the nozzle heads, substantially as illustrated inFIGS. 16 and 17. A gasket 198 situated in between the reinforcing andbacking plates mitigates leakage of the pressure box 174 and ensuressustained and continuous pressure thereat for passing of the aqueouscleaning solution through the nozzle head 58 and forcibly into theinterior chamber 28.

Referring now to FIGS. 10 and 11, the drain box 168 generally extendsthe full width of the side wall of the retention tank 20 and comprisesan intake side 200 and a bottom 202 coinciding with the base. An outletopening 204 extending through the bottom of the drain box receives anoutlet line 206 extending therefrom and terminating at an intake side208 of the pump, as denoted by path C in FIG. 18. A water input opening210 extending through the bottom 202 suitably receives a fitting 212 forconnecting pipe therefrom to a ball valve 214 primarily serving as meansfor feeding fresh water from an external water source 215 into the drainbox 168 and subsequently into the retention tank 20, as denoted by pathsA and B in FIG. 18. Like the second end of the intake piping, the intakeside 200 is suitably fitted with a screen 216 to inhibit the passage ofsmall rapid prototype parts and residual support material into andthrough the drain box, pump and ball valve, yet affording continuouspassage of the aqueous cleaning solution. Like the embodimentillustrated in FIGS. 1-9, the retention tank 20 of the alternativeembodiment comprises a thermocouple 218 having an internal probe 218 apositioned within the drain box for measuring the ambient temperature ofthe aqueous cleaning solution and controlling heat inputs to themicroprocessor and a heating element 220 having an internal end 220 a ofthe band type suitably situated near the base and housed in a heatchamber 221 substantially extending about the width of the side wall 22and placed opposite to the location of the drain box 168, below the boxmanifold, and an external end 220 b communicatively coupled to themicroprocessor 124. A screen 221 a similar to the one attached on theintake side of the drain box is mounted to an elongate opening 221 b ofthe heat chamber. The retention tank of the embodiment shown in FIGS.10-22 further comprises a level indicator 222 to the likes discussed foruse with the embodiment shown in FIGS. 1-9, particularly of the typesubstantially capable of measuring the level of the aqueous cleaningsolution within the interior chamber 28 to ensure inoperative status ofthe pump 52 in the event that the solution level is inadequate tosupport flow through the pump and box manifold and further ensure thateach nozzle head is situated below the solution level. As respectivelydenoted by paths D and F in FIG. 18, the three-way ball valve 184further comprises an intake stem 224 hydraulically connected to adischarge side 226 of the pump and a drain stem 228 a hydraulicallyconnected to an external drain line 228 b, which collectively serve incirculating and removing the aqueous cleaning solution in and from theinterior chamber 28. Although operation of the embodiment shown in FIGS.10-22 is substantially similar to the embodiment shown in FIGS. 1-9 interms of controlling temperature, flow and time functions, theembodiment shown in FIGS. 10-22 further comprises a three-positionselector switch 229 having operable modes designated as off, cleanparts, and drain tank, as best illustrated in FIG. 19. In the cleanparts mode, the embodiment shown in FIGS. 10-22 functions similarly tothe preferred embodiment with exception that the user can locallyoperate the incoming water supply by manually turning a handle 230 madepart of the ball valve 214 in the direction of flow, after which thetank fills with the aqueous cleaning solution to a predetermined level.Time inputs are subsequently entered into the microprocessor 124 via theinterface controller and the controller start button is activated topower the heating element and pump for a set duration of time. The drainmode primarily serves as means for bypassing the microprocessor 124insofar to simultaneously activate the pump 58 and a magnetic switch 231made integrally part of the three-way ball valve to direct flowoutwardly from the retention tank via path F in FIG. 18.

Like the embodiment shown in FIGS. 1-9, the embodiment shown in FIGS.10-22 can be fitted with a work surface 138 having recessed features andmeans to mitigate evaporative loss of the aqueous cleaning solutionduring operation. Further, the embodiment shown in FIGS. 10-22 can behoused in a cabinet 14 to the likes described for the embodiment shownin FIGS. 1-9. Alternatively, as shown in FIG. 20, the embodiments shownin FIGS. 1-9 and 10-22 may be suitably housed in a storage cabinet 232having accessible storage capacity 234, an integral work platform 236and a localized water source 238 and drain hydraulically connected to anexternal water supply and drain line, respectively. In thisconfiguration, the retention tank 20 comprises a mounting flange 240extending outwardly from and along an upper perimeter 242 integrallymade part thereof, which substantially serves as means for securing andattaching the retention tank to the integral work platform of thestorage cabinet. In mitigating evaporative loss to the likes of thecabinet used for the embodiment shown in FIGS. 1-9, the storage cabinet232 may comprise a cover 244 having a hinge 246 mounted along its backleading edge and a handle 248 attached to an exterior surface 250thereof. A backstop 252 fixedly mounted to the work platform 236suitably serves in controlling the extent to which the cover movesbeyond the location of the cover's hinge and provides means formaintaining the vertical orientation of a drop basket 254 alternativelymade part of the cover, particularly of the type shown in FIG. 21. Apair of sliding brackets 256 each having a movable slide bar 258 toengage an opening 260 extending through an end wall of the back stopserves as means for locking the cover to the back top 252 in asubstantial vertical orientation. The drop basket 254, as shown in FIGS.21 and 22, comprises an overall rectangular configuration having a toplid 262 hingedly attached to one corner thereof and secured in place bya frontal latch 264 engaging a s-shaped member 266 mounted to a frontside 268 of the drop basket. A pair of handles 270 mounted to anexterior surface 272 of the top lid 262 serves as means for lifting andlowering the top lid from and to the drop basket 254. Mounting of thedrop basket to the cover 244 is primarily accomplished by upwardly anddownwardly orientated lip brackets 274 a, 274 b configured in such amanner to slidably engage and lock with one another. As shownspecifically in FIG. 22, the upwardly orientated lip bracket is attachedto a backside of the cover 244 and engages the downwardly orientated lipbracket as attached to a backside of the drop basket.

It can be seen from the foregoing that there is provided in accordancewith this disclosure a simple and easily operated device, which isparticularly suited to operate side-by-side with a rapid prototype partsmaking machine in an office setting or similarly suited environment. Thesupport removal apparatus 10 is completely functional in removing watersoluble supports efficiently from rapid prototype parts given suitableoperability in terms of aqueous cleaning solution type andconcentration, agitation, and temperature.

The components comprising the support removal apparatus may befabricated from a variety of materials, providing such selection or useof materials possess the capacity to withstand premature corrosion giventhe presence and use of an alkaline aqueous cleaning solution, notablyfalling within an applicable pH range of 8-11. Accordingly, it may bedesirable to construct the retention tank 20, work surface 138, lid 148and nozzle heads 58 from 316 stainless steel, pipe and fittings from apolymeric material such as polyamide (PA) oracrylonitrile-butadiene-styrene (ABS), and cabinet 14 and storagecabinet 232 from a lower grade stainless steel. It is noted herein thatthe retention tank, nozzle head, work surface, and integral workplatform may be alternatively fabricated from materials to lessen theoverall weight of the support removal apparatus yet maintainingsufficient resistance to corrosion, such as polypropylene,polyoxymethylene, polyphenylene, ABS, or PA. Similarly, the pump,thermocouple, heating element, and level indictor, particularly exposedoperable components of each, are fabricated from a high grade stainlesssteel (316) or coated with an impervious, corrosive-resistant materialsuch as epoxy.

According to another embodiment, a container can be used to improve theefficiency of the process of removing soluble support material from arapid prototype part. FIG. 23 is a system diagram illustrating a system300 for removing soluble support material from a rapid prototype partusing an aqueous cleaning solution. The system 300 includes a container302, which is discussed in greater detail below in connection with FIGS.24-28. Another implementation of the container 302 is depicted in anddiscussed below in connection with FIG. 29. The container 302 defines avolume for receiving the rapid prototype part (not shown in FIG. 23) andhas an inlet port 304 and an outlet port 306. A sealing arrangement 308,such as a clamp, substantially seals the container 302 after the rapidprototype part has been placed inside the container 302. With thecontainer 302 substantially sealed in this way, the aqueous cleaningsolution is substantially prevented from leaking out of the container302 as it flows through the container 302.

A basin 310 stores the aqueous cleaning solution. By way of example andnot limitation, the aqueous cleaning solution may comprise alcohol,sodium hydroxide, or potassium hydroxide. The basin may be formed of anymaterial that is compatible with the aqueous cleaning solution, such asa polymer or a metal. The basin 310 has an inlet port 312 and a drainbasket 314. A pump 316 is connected in fluid communication with thebasin 310. In operation, the pump 316 pumps the aqueous cleaningsolution from the basin 310 through tubing 318 and 320 and into thecontainer 302 via the inlet port 304, which is coupled to the tubing320, and thus to the pump 316, by a connector 322. The connector 322 maybe implemented as a quick coupler type connector. The tubing 318 and 320and the connector 322 may be formed from any material that is compatiblewith the aqueous cleaning solution, i.e., by any material that will notbe damaged by exposure to the aqueous cleaning solution.

The aqueous cleaning solution removes the soluble support material fromthe rapid prototype part and is discharged from the container 302through the outlet port 306. The outlet port 306 is connected in fluidcommunication with the basin 310 via a connector 324 that is coupled tooutlet port 306 and to tubing 326, which may be formed from any materialthat is compatible with the aqueous cleaning solution. The connector 324may be implemented as a quick coupler type connector. The aqueouscleaning solution flows through the tubing 326 and reenters the basin310 through the inlet port 312. After the aqueous cleaning solutionreenters the basin 310, it is once again pumped out of the basin 310 bythe pump 316 through the drain basket 314. The drain basket 314 mayincorporate a mesh screen or other filter for filtering out particles ofsoluble support material that were removed from the rapid prototypepart.

In some embodiments, the aqueous cleaning solution is heated to improveits efficiency in removing soluble support material. For example, theaqueous cleaning solution may be heated to a temperature between 50degrees Fahrenheit and 200 degrees Fahrenheit. Heating the solution canbe accomplished using a heater 328 disposed within the basin 310. Itwill be appreciated by those of skill in the art that, if the basin 310is formed from a material having a relatively low melting point, such ascertain polymers, it may be desirable to employ a circulation heater(not shown) disposed around, for example, tubing 326, in lieu of theheater 328 disposed within the basin 310 in order to avoid damaging thebasin 310.

FIG. 24 and FIG. 25 are perspective views of one example implementationof the container 302. The container 302 includes a liner 400 that has anexterior surface. The liner 400 may be formed from any of a variety ofchemically resistant materials, i.e., materials that will not be damagedby the aqueous cleaning solution. By way of example and not limitation,the liner 400 may be formed from nylon, a polyolefin such aspolypropylene, or a fluoropolymer such as PTFE, TEFLON®, or FEP. It isdesirable that the liner 400 is resistant both to the chemicals used inremoving the soluble support material or substrate and to thetemperatures involved in the process. It is also desirable that theliner 400 is degradable. Alternatively, the liner 400 could incorporateless chemically resistant materials, such as ABS or PVC. In suchembodiments, the liner 400 would degrade after a number of uses andwould need to be replaced.

In the embodiment of FIGS. 24 and 25, the liner 400 is expandable todefine a mouth portion 402 at one end and is heat sealed at the oppositeend 404. When the liner 400 is expanded, the liner 400 defines a volumeinto which the rapid prototype part (not shown in FIG. 24) can bereceived. After the rapid prototype part is received in the container302, the sealing arrangement 308 substantially seals the mouth portion402 so that the aqueous cleaning solution is substantially preventedfrom leaking out of the mouth portion 402.

In the embodiment shown in FIG. 24, the inlet port 304 and the outletport 306 are heat sealed on the other two sides of the exterior surfaceof the liner 400. Alternatively, the inlet port 304 and the outlet port306 may be affixed to or formed on the exterior surface of the liner 400by any suitable process, including, for example, insert molding. Boththe inlet port 304 and the outlet port 306 are in fluid communicationwith the volume defined when the liner 400 is expanded. In operation,the aqueous cleaning solution is introduced into the volume through theinlet port 304, which is in fluid communication with the basin 310storing the aqueous cleaning solution via the tubing 318 and 320 and theconnector 322. In one example embodiment, the aqueous cleaning solutionis supplied to the inlet port 304 at a pressure of approximately 3-60pounds per square inch (psi). The aqueous cleaning solution removes thesoluble support material from the rapid prototype part and is dischargedfrom the container 302 through the outlet port 306, which is connectedto the tubing 326 via the connector 324. As the aqueous cleaningsolution flows out of the container 302, it may carry the removedsoluble support material with it through the tubing 326 back to thebasin 310, where the removed soluble support material is filtered by thedrain basket 314 before the aqueous cleaning solution is pumped back tothe container 302.

FIGS. 26 and 27 are additional perspective views of the container 302 ofFIGS. 24-25. FIG. 26 shows the liner 400 and the mouth portion 402having been expanded to define a volume 410 for receiving a rapidprototype part 412 having aqueous soluble support material deposited onit. FIG. 27 illustrates the sealing arrangement 308 as detached from thecontainer 302. It will be appreciated by those of skill in the art thatthe container 302 may be sealed by folding or crimping the mouth portion402 of the liner 400 and engaging the sealing arrangement 308.

FIG. 28 is a side view of one example embodiment of the sealingarrangement 308. In the embodiment of FIG. 28, the sealing arrangement308 is implemented as a clamp. The clamp has a clamp body 430 into whichthe folded or crimped mouth portion 402 of the liner 400 is placed.After the mouth portion 402 has been placed in the clamp body 430, oneor more thumbscrews 432 are tightened to compress the folded or crimpedmouth portion 402 and thereby substantially seal the mouth portion 402.In this way, a substantially airtight and watertight seal is provided,and leakage of the aqueous cleaning solution from the mouth portion 402is substantially prevented. While a single thumbscrew 432 is visible inthe side view of FIG. 28, it will be appreciated that multiplethumbscrews 432 may be employed, as shown in FIGS. 23-25, 27, and 29.

The efficiency of the cleaning process by which the aqueous cleaningsolution removes the soluble support material from the rapid prototypepart is affected by a number of factors, including, but not limited to,the concentration of the aqueous cleaning solution, the temperature ofthe aqueous cleaning solution, the duration for which the rapidprototype part is subjected to the cleaning process, the flow rate atwhich the aqueous cleaning solution is supplied to the container 302,and any pressure differential between the inlet port 304 and the outletport 306.

As mentioned above, one factor affecting the efficiency of the cleaningprocess is the existence of a pressure differential between the inletport 304 and the outlet port 306. The pressure differential is afunction of the difference in cross-sectional area between the inletport 304 and the outlet port 306. No effect on efficiency has beenobserved in embodiments in which the diameter, and therefore thecross-sectional area, of the outlet port 306 is larger than that of theinlet port 304. Surprisingly, however, when the diameter of the outletport 306 is the same size as or smaller than the diameter of the inletport 304, an improvement in efficiency of 100%-300% has been observed;in such embodiments, the cleaning process has been observed to becompleted substantially more quickly relative to embodiments in whichthe outlet port 306 is larger than the inlet port 304. It ishypothesized that when the outlet port 306 is smaller than the inletport 304, pressure is created inside the container 302, resulting infaster agitation of the soluble support material from the rapidprototype part.

Another way of increasing the effective cross sectional area of theinlet port 304 or the outlet port 306 is to employ multiple inlet ports304 or multiple outlet ports 306, or both. FIG. 29 is a perspective viewof a container 450 having multiple inlet ports 452 and multiple outletports 454 according to still another embodiment. The container 450 maybe substituted for the container 302 in the system 300, with appropriatemodifications to the system 300 to accommodate the multiple inlet ports452 and/or multiple outlet ports 454. For example, additional tubingsimilar to tubing 320 and 326 and additional connectors similar toconnectors 322 and 324 may be required. Alternatively, manifolds may beused to connect multiple inlet ports 452 or multiple outlet ports 454 toa single connector or tubing. It will be appreciated that, while FIG. 29depicts two inlet ports 452 and two outlet ports 454 and FIGS. 23-28depict a single inlet port 304 and a single outlet port 306, someembodiments may employ a single inlet port and multiple outlet ports or,conversely, multiple inlet ports and a single outlet port. In short, anynumber of inlet ports and outlet ports, in any combination, may beemployed.

The embodiments described herein may result in certain advantagesrelative to the prior art. For instance, it has been observed that underotherwise comparable conditions, e.g., similar temperature conditionsand similar concentrations of aqueous cleaning solution, the time toremove soluble support material from a rapid prototype part can bereduced from, for example, five or more hours to approximately 30minutes. This increased efficiency can result in increased throughput.Further, the container used in the process is relatively easy tomanufacture and assemble and can be retrofitted on existing equipment.Accordingly, little, if any, modification is required to existingequipment.

It is to be understood that even though numerous characteristics andadvantages of various embodiments have been set forth in thedescription, together with details of the structure and function ofvarious embodiments, this disclosure is illustrative only, and changesmay be made in detail, especially in matters of structure andarrangement of parts within the principles described herein to the fullextent indicated by the broad general meaning of the terms in which theappended claims are expressed. For example, the container 302 may bemanufactured by blow molding or other suitable processes, in which casethe end 404 of the liner 400 may not be heat sealed and the container302 may not contain any seams.

1. A container comprising: a liner having an exterior surface andexpandable to define a mouth portion and a volume for receiving, via themouth portion, a rapid prototype part having soluble support materialdeposited thereon; an inlet port formed on the exterior surface and influid communication with the volume; an outlet port formed on theexterior surface and in fluid communication with the volume; and asealing arrangement configured and arranged to selectively substantiallyprevent egress of an aqueous cleaning solution from the mouth portion ofthe liner, wherein the inlet port is configured to introduce the aqueouscleaning solution into the volume to remove the soluble support materialfrom the rapid prototype part.
 2. The container of claim 1, wherein theoutlet port has a diameter that is not larger than a diameter of theinlet port.
 3. The container of claim 1, further comprising a pluralityof inlet ports formed on the exterior surface of the container.
 4. Thecontainer of claim 1, further comprising a plurality of outlet portsformed on the exterior surface of the container.
 5. The container ofclaim 1, further comprising at least one quick connect type connectorconnected to at least one of the inlet port and the outlet port.
 6. Thecontainer of claim 1, wherein the liner is formed from a materialselected from the group consisting of ABS, PVC, a polyolefin, nylon, anda fluoropolymer.
 7. A method of removing soluble support material from arapid prototype part, the method comprising: placing the rapid prototypepart in a container having an inlet port and an outlet port;substantially sealing the container to selectively substantially preventegress of an aqueous cleaning solution from the container; connectingthe first port to a supply of the aqueous cleaning solution; introducingthe aqueous cleaning solution into the container via the inlet port,thereby removing the soluble support material from the rapid prototypepart; and evacuating the aqueous cleaning solution from the containervia the outlet port.
 8. The method of claim 7, wherein the outlet porthas a diameter that is not larger than a diameter of the inlet port. 9.The method of claim 7, wherein the container comprises a plurality ofinlet ports formed on an exterior surface of the container.
 10. Themethod of claim 7, wherein the container comprises a plurality of outletports formed on an exterior surface of the container.
 11. The method ofclaim 7, wherein the container comprises at least one quick connect typeconnector connected to at least one of the inlet port and the outletport.
 12. The method of claim 7, further comprising supplying theaqueous cleaning solution to the first port at a pressure in the rangeof 3 pounds per square inch (psi) to 60 psi.
 13. The method of claim 7,further comprising heating the aqueous cleaning solution to atemperature in the range of 50 degrees Fahrenheit to 200 degreesFahrenheit.
 14. A system for removing soluble support material from arapid prototype part, the system comprising: a basin having an inletport and a drain basket and configured to store an aqueous cleaningsolution; a container comprising a liner having an exterior surface andexpandable to define a mouth portion and a volume for receiving, via themouth portion, a rapid prototype part having soluble support materialdeposited thereon; an inlet port formed on the exterior surface and influid communication with the volume; an outlet port formed on theexterior surface and in fluid communication with the volume and with theinlet port of the basin; and a sealing arrangement configured andarranged to selectively substantially prevent egress of an aqueouscleaning solution from the mouth portion of the liner; a pump in fluidcommunication with the basin and with the inlet port of the containerand configured to pump the aqueous cleaning solution from the basin intothe volume defined by the liner of the container and back to the basin;whereby, when the pump is actuated, the aqueous cleaning solution isintroduced into the volume defined by the liner of the container toremove the soluble support material from the rapid prototype part. 15.The system of claim 14, wherein the outlet port of the container has adiameter that is not larger than a diameter of the inlet port of thecontainer.
 16. The system of claim 14, wherein the container has aplurality of inlet ports formed on the exterior surface of the liner.17. The system of claim 14, wherein the container has a plurality ofoutlet ports formed on the exterior surface of the liner.
 18. The systemof claim 14, further comprising at least one quick coupler typeconnector in fluid communication with at least one of the inlet port ofthe container and the outlet port of the container.
 19. The system ofclaim 14, wherein the liner is formed from a material selected from thegroup consisting of a polyolefin, nylon, and a fluoropolymer.
 20. Thesystem of claim 14, further comprising a heater configured to heat theaqueous cleaning solution to a temperature in the range of 50 degreesFahrenheit to 200 degrees Fahrenheit.